by Michelle Healy, USA TODAY

by Michelle Healy, USA TODAY

An updated schedule of recommended children's vaccinations, published today in the journal Pediatrics, aims to clarify and simplify the list of shots that kids need to stay healthy and avoid preventable diseases.

The 2013 edition of that guide, the Recommended Childhood and Adolescent Immunization Schedule, has been approved by the American Academy of Pediatrics, the Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention, and the American Academy of Family Physicians. The schedule features several changes from the 2012 edition, including a redesigned layout, allowing for easier reading and more room for clarification in the footnotes, says H. Cody Meissner, a pediatric infectious-disease specialist at Tufts Medical Center and a contributor to the statement.

Also, a single schedule for kids up to age 18 replaces separate schedules for children 6 and under, and kids ages 7 to 18.

Key among the vaccination changes is the new recommendation that pregnant women or teens be given the combined tetanus, diphtheria and acellular pertussis (Tdap) vaccination during each pregnancy to protect their infant from pertussis (whooping cough), even if they have previously had a Tdap shot.

"The rationale is that by vaccinating the mother during pregnancy, she'll make antibodies that will cross the placenta and pass to the baby," says Meissner. This will give infants protection "for the first few months of life, when they are too young" to get their own shots, he says.

The CDC adopted the recommendation in December in response to the dramatic increase in the number of whooping cough cases and outbreaks across the country. The highly contagious respiratory disease is marked by uncontrollable, violent coughing that makes it difficult to breathe. It most commonly affects infants and young children and can be fatal, especially in babies under 1 year.